Driving apparatus for valves of internal combustion engines

ABSTRACT

In an internal combustion engine of the type wherein the suction and exhaust valves are operated by a valve operating mechanism housed in a cover, the valve operating mechanism comprises a plurality of rocking arms pivotally supported by the cover, rod means interposed between one end of the rocking arms and the valve stems of the suction and exhaust valves for opening and closing the same and means for permitting lateral movement to the rod means with respect to the valve stems in accordance with the rocking motion of the rocking arms. The cover is supported by a cylindrical support disposed within a circle on which a plurality of bolts adapted to secure the cylinder head to a cylinder block are arranged, and the cover is removably secured to the cylinder head.

United States Patent [1.91

Ishida et a1.

[ DRIVING APPARATUS FOR VALVES OF INTERNAL COMBUSTION ENGINES [75] Inventors: Naoyoshi I'shida; Atsushi Watanabe;

Yukio Ishii, all of Tamano, Japan [73] Assignee: Japan Ships Machinery Development Association, Tokyo, Japan 22 Filed: Sept. 29, 1972,

21 Appl. No.: 293,426

[30] Foreign Application Priority Data [11] 3,821,942 [451 "July 2,1974

Primary Examiner-Manuel A. Antonakas Assistant ExaminerDaniel J. OConnor Attorney, Agent, or FirmChittick, Thompson & Pfund [5 7] ABSTRACT In an internal combustion engine of the type wherein the suction and exhaust valves are operated by a valve operating mechanism housed in a cover, the valve operating mechanism comprises a plurality of rocking arms pivotally supported by the cover, rod means interposed between one end of the rocking arms and the valve stems of the suction and exhaust valves for opening and closing the same and means for permitting lateral movement to the rod means with respect to the valve stems in accordance with the rocking motion of the rocking arms. The cover is supported by a cylindrical support disposed within a circle on which a plurality of bolts adapted to secure the cylinder head to a cylinder block are arranged, and the cover is removably secured to the cylinder head.

3 Claims, 2 Drawing Figures PAIENTEDJUL 2 I974 SHEET 2 0F 2 F/GZ DRIVING APPARATUS FOR VALVES OF INTERNAL COMBUSTION ENGINES BACKGROUND OF THE INVENTION This invention relates to an internal combustion engine, and more particularly to improved suction and exhaust valve operating mechanism and a cylinder cover.

Generally, in a valve operating mechanism in which rocking arms are used to open and close the suction and exhaust valves, the rocking arms are urged directly against the valve heads. Consequently, when the valves are operated in the vertical direction by the rocking or arcuate motion of the rocking arms an undesirable force or the horizontal component of the movement of the rocking arms is applied to the valve heads and valve stems, thus causing a great wear of these elements. Although such wear can be decreased by oiling, since these elements are heated to high temperatures, oil causes seizure.

Furthermore, in a large size internal combustion engine installed in a ship, for example, a cylinder cover for protecting the valves and their operating mechanism is bolted to the cylinder head. Accordingly, where it is necessary to dismount a piston or the like component parts it is necessary to remove the cover and the valve operating mechanism before removing a plurality of bolts which are used to clamp a cylinder head to a cylinder block. Such removal of numerous component parts for performing dismounting and repair of a limited number of the component parts requires a large amount of labour and time. This is especially true where the size of the engine is large and where the space available for this service is limited as in a ship.

SUMMARY OF THE INVENTION Accordingly, it is an object of this invention to provide an improved valve operating mechanism which can prevent the horizontal component of the rocking movement of the rocking arm from acting upon the valve stems of the suction and exhaust valves thereby preventing the wear of the valve stems.

Another object of this invention is to provide an improved internal combustion engine which can be readily disassembled with minimum labour.

A further object of this invention is to provide an improved internal combustion engine wherein the cylinder cover can be readily dismounted from the engine block. v

According to one aspect of the invention there is provided an internal combustion engine of the type wherein the suction and exhaust valves are operated by a valve operating mechanism mounted on a cylinder head which is bolted to a cylinder block, and the valve operating mechanism is housed in a cover, characterized in that the valve operating mechanism comprises a plurality of pivotally mounted rocking arms, means for rocking the rocking arms, rod means interposed between one end of the rocking arms and the valve stems of the suction and exhaust valves for opening and closing the same, and means for permitting lateral movement to the rod means with respect to the valve stems in accordance with the rocking motion of the rocking arms.

According to another aspect of the invention there is provided an internal combustion engine of the type wherein the suction and exhaust valves are operated by BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings:

FIG. 1 shows a longitudinal sectional view of the upper portion of an internal combustion engine embodying the invention and FIG. 2 is a plan view of the engine shown in FIG. 1

, with the lid of the cylindrical cover removed.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to FIG. 1 of the accompanying drawing, the internal combustion engine 30 comprises a cylinder block 31 containing a piston 32, a cylinder head 1 and a valve operating mechanism 2'. The cylinder head 1 is provided with a suction opening 3 and an exhaust opening 4 which are controlled by a suction valve 5 and an exhaust valve 6 respectively. The valve stems 5a and 6a of these valves are guided by valve guides 7 and 8 of cast iron which are secured to the cylinder head 1. As shown in FIG. 2, a fuel injection nozzle 33 is also mounted on the cylinder head 1. Near the upper ends of the valve stems 5a and 5b are secured spring seats 9 and 10, and springs l I and 12 are interposed between the spring seats 9 and 10 and the flanges at the lower ends of the valve guides 7 and 8 to normally urge the suction and exhaust valves 5 and 6 toward the closed positions. Rods 13 and 14 are supported by holders 15 and 16, respectively, above valve stems 5a and 6a to be operated in unison therewith. The holders 15 and 16 are supported by a cover 34. Rocking arms 19 and 20 are pivotally mounted on pivot shaft 17 and 18 respectively which are supported by the cover 34. At one ends of the rocking arms 19 and 20 are secured thrust screws2l and 22 with their spherical lower ends received in the sockets formed on the upper surfaces of intermediate members 26 and 27. The thrust screws 21 and 22 are provided with screw threads and are secured to the rocking arms 19 and 20 by means of nuts 23 and 24 so as to adjust the valve openings. The other ends of the rocking arms 19 and 20 are moved in the vertical direction by means of cams, not shown, through operating rods 25.

As one of the rods 25 is raised by the cam, rocking arm 20 is rotated in the counterclockwise direction to open the exhaust valve -6 through thrust screw 22 and rod 14. The horizontal displacement of the push rod 22 is absorbed by the horizontal sliding movement of the intermediate member 27 relative to the upper end of rod 14. To permit this relative movement the diameter of the intermediate member 27 may be made smaller than that of the rod 14. When rod 25 is moved downward, the valve stem 6a, rods 14 and 22 are urged upward by the action of spring 12 to rotate the rocking arms 20 in the clockwise direction, thus closing the exhaust valve 6. It will be clear that the suction valve 5 is operated similarly.

As above described, according to this invention, the rotary movement of the rocking arms is transmitted to the suction and exhaust valves through rods that can move relatively in the horizontal direction so that the horizontal component of the rotary movement of the rocking arms is not transmitted to the suction and exhaust valves, thus preventing undesirable wear of the stems thereof. When the rods 13 and 14 wear out it is possible to readily exchange them without disassembling the cylinder head or the valve operating mechanism.

According to another feature of this invention, a cylindrical support 43 is mounted on the cylinder head 1 within a circle on which the bolts 40 for securing the cylinder head 1 to the cylinder block 31 are disposed. A cylindrical cover 34 having a projection 45 for supporting the rocking arms 19 and 20 is mounted on the support 43. The cover 34 is secured to the cylinder head 1 by means of a plurality of bolts 46. The cover 34 is provided with a removable lid 47.

Upon occurrence of a fault which required dismounting of the cylinder cover 1, the lid 47 is removed and then the cover 34 is removed together with the valve operating mechanism 2 by removing bolts 46. Then,

bolts 40 are removed for enabling dismounting of the cylinder head 1. Thus the disassembly of the engine is greatly simplified.

What is claimed is:

1. In an internal combustion engine of the type wherein the suction and exhaust valves having valve stems are operated by a valve operating mechanism mounted on a cylinder head which is bolted to a cylinder block and the valve operating mechanism is housed in a cover, the improvement wherein said valve operating mechanism comprises a plurality of rocking arms pivotally mounted to said cover with thrust screws at one end of said rocking arms, means for rocking said rocking arms, and rod means interposed between said thrust screws and said valve stems of said suction and exhaust valves for transmitting axial motion for opening and closing said valves, wherein each rod means comprises an intermediate member connected to the end of said thrust screw, a rod interposed between said intermediate member and said valve stem and stationary means for guiding the vertical movement of said rod, said stationary meanshbeing supported by said cover.

2. In an internal combustion engine of the type wherein suction and exhaust valves are operated by a valve operating mechanism mounted on a cylinder head which is bolted to a cylinder block and the valve operating mechanism is housed in a cover, the improvement which comprises a cylindrical support disposed within a circle on which a plurality of bolts adapted to secure said cylinder head to a cylinder block are arranged, said support supporting said cover, and means for removably securing said cover to said cylinder head, said valve operating mechanism comprising a plurality of rocking armspivotally supported by said cover, means for rocking said rocking arms, rod means interposed between one end of each of said rocking arms and the valve stems of said suction and exhaust valves guided for transmitting axial motion for opening and closing said valves, said last named means comprising a laterally movable rod portion intermediate said one end and said valve stem.

3. In an internal combustion engine of the type wherein the suction and exhaust valves are operated by a valve operating mechanism mounted on a cylinder head which is bolted to a cylinder block and the valve operating mechanism is housed in a cover, the improvement wherein said valve operating mechanism comprises a plurality of pivotally mounted rocking arms, means for rocking said rocking arms and, rod means interposed between one end of said rocking arms and the valve stems of said suction and exhaust valves for opening and closing said valves, wherein each rod means comprises a push member adjustably mounted on one end of said rocking arm, an intermediate member connected to thev lower end of said push member through a ball and socket joint, a rod interposed between the valve stem of each of said suction and exhaust valves and said intermediate member, and stationary means supported by said cover for guiding the vertical movement of said rod.

UNITED STATES PATENT AND TRADEMARK OFFICE CERTIFICATE OF CORRECTION PATENT NO. 3 2

DATED July 2 1974 0 (5) Naoyoshi Ishida, Atsushi Watanabe, and Yukio Ishii It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In the legend: "[73] Assignee: Japan Ship's Machinery Development Association, Tokyo, Japan" should read:-

- [73] Assignee: Mitsui Shipbuilding & Engineering Co. Ltd. Japan Ship's Machinery Development Association, Tokyo, Japan Signed and Scaled this Tenth D3) 0fv May 1977 [SEAL] ANESI.

RUTH C. MASON Arresting Officer C. MARSHALL DANN Commissioner ofI-atenrs and Trademarks 

1. In an internal combustion engine of the type wherein the suction and exhaust valves having valve stems are operated by a valve operating mechanism mounted on a cylinder head which is bolted to a cylinder block and the valve operating mechanism is housed in a cover, the improvement wherein said valve operating mechanism comprises a plurality of rocking arms pivotally mounted to said cover with thrust screws at one end of said rocking arms, means for rocking said rocking arms, and rod means interposed between said thrust screws and said valve stems of said suction and exhaust valves for transmitting axial motion for opening and closing said valves, wherein each rod means comprises an intermediate member connected to the end of said thrust screw, a rod interposed between said intermediate member and said valve stem and stationary means for guiding the vertical movement of said rod, said stationary means being supported by said cover.
 2. In an internal combustion engine of the type wherein suction and exhaust valves are operated by a valve operating mechanism mounted on a cylinder head which is bolted to a cylinder block and the valve operating mechanism is housed in a cover, the improvement which comprises a cylindrical support disposed within a circle on which a plurality of bolts adapted to secure said cylinder head to a cylinder block are arranged, said support supporting said cover, and means for removably securing said cover to said cylinder head, said valve operating mechanism comprising a plurality of rocking arms pivotally supported by said cover, means for rocking said rocking arms, rod means interposed between one end of each of said rocking arms and the valve stems of said suction and exhaust valves guided for transmitting axial motion for opening and closing said valves, said last named means comprising a laterally movable rod portion intermediate said one end and said valve stem.
 3. In an internal combustion engine of the type wherein the suction and exhaust valves are operated by a valve operating mechanism mounted on a cylinder head which is bolted to a cylinder block and the valve operating mechanism is housed in a cover, the improvement wherein said valve operating mechanism comprises a plurality of pivotally mounted rocking arms, means for rocking said rocking arms and, rod means interposed between one end of said rocking arms and the valve stems of said suction and exhaust valves for opening and closing said valves, wherein each rod means comprises a push member adjustably mounted on one end of said rocking arm, an inteRmediate member connected to the lower end of said push member through a ball and socket joint, a rod interposed between the valve stem of each of said suction and exhaust valves and said intermediate member, and stationary means supported by said cover for guiding the vertical movement of said rod. 